exgtinows4

My 2011 GTS has PSE. however I find the sound to be lacking compared to my C2S which has the gundo hack. This has me thinking if the PSE is truly working at 100%. It certainly adds sounds when switched on ( mostly above 3-4k)... And maybe that's the difference... Since I don't drive over 4k a lot I notice the gundo hack more?

Buddhamonk

remember that the 997.2 has a center muffler. That's why Gundo on a 997.2 doesn't work as well as gundo on a 997.1

Also gundo is a true bypass where the air does not even go through the muffler. With PSE, air flow still goes through the muffler but takes a different pathway. Gundo will always be louder than OEM PSE

golftime

PSE on my 996 was much more pronounced than my 997.2. I don't think either one had anything wrong with them, and I am not sure why, but they are just different.

exgtinows4

Anyone experiment with gundo on PSE?is it possible?

Buddhamonk

been done but won't be as loud because of the center muffler. Center muffler delete is probably your best mod if you want a louder sounding 997.2 that is already equipped with PSE

bmwfan328

IIRC, the PSE is programmed to close the valves between certain RPM ranges to satisfy European noise restrictions for normal city driving conditions (~2K > 4K RPM). In contrast, the Gundo Hack is always on, probably accounting for most of the difference in volume between the two below 4K RPM

exgtinows4

I do have an AWE bypass... Still not loving it. Who has done gundo on a PSE? Is it a straight fix like non PSE?

Petza914

You'd probably come out ahead by selling your PSE mufflers, acquiring stock ones, and then hacking those. PSE mufflers are worth a fair amount whereas stock non-PSE cans aren't, or just go with a valved aftermarket version and something like a Sharkwerks or Fabspeed bypass of the center muffler.

exgtinows4

That's a great idea. Anyone wanting a trade for 997.2s mufflers please PM me!

Buddhamonk

sounds like what you really need are muffler bypass pipes...sounds awesome

exgtinows4

I have read that the primary muffler bypass pipes are loud and not very deep

St8haus

Did the center muffler bypass on my 997.2 with PSE (no Gundo) and LOVE the sound...easy install and changed the tune a lot! Might want to start there...

exgtinows4

Already have a center bypass... Still want more... Its not equal to gundo + bypass....

John@Fabspeed

Don't forget you have a whole other area of the exhaust system that you haven't touched yet...the factory headers! Factory headers not only restrict a nice chunk of horsepower, but sound as well. Think of your cats as mufflers, when you have a factory cat core that depending on the car averages 600-800cells per square inch in density...there is quite a sound improvement when you optimize the header design with our Sport Headers, which utilize HJS 200cell cat cores. That is a lot less cat restriction, and therefore less sound restriction as well. Sound level will go up a noticeable amount, and as you progress through into the higher rpms you'll get a bit more exotic/higher pitch to the exhaust note. The cherry on top is a nice boost in the powercurve, especially through the low-end/mid range.

You PSE mufflers are a great commodity to have, and quite valuable with the car. I am quite confident that upgrading your headers is going to meet your sound goals and maintain that nice valved mild-to wild option for you

Fined

I found PSE on the GTS to be pitiful. I had a sharkwerks bypass on the way as soon as I got the car. I'd advise making exhaust changes one bit at a time, so you can figure out exactly what you want in sound with the least spending. I also would recommend doing the least invasive changes you can to start. I did a PSE disable (so its always as open as it can get) and a bypass of the 3rd muffler right away. Now I see its still not enough for me, so I'll be doing the headers/cats next year.

Make sure to shop around. Not every vendor has folks on the board responding to threads to push product.